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A free, fun platform for learning modern cryptography

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Learn By Doing

Learn about modern cryptography by solving a series of interactive puzzles and challenges. Get to know the ciphers and protocols that secure the digital world by breaking them.

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Level Up

Earn points by solving challenges. Finish categories to earn trophies and gain levels to track your progress. Can you reach the top of the scoreboard?

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Fresh Challenges

We are constantly creating new challenges to keep your crypto knowledge up to date. Expect exciting brainteasers and whole new categories as the site continues to grow.

New Challenges
Blind (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up (ECSC 2023 (Norway)) CTF Archive 0
Irish flan (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up 2 (ECSC 2023 (Norway)) CTF Archive 0
Twist and shout (ECSC 2023 (Norway)) CTF Archive 0
Weekly Top Users
#1 Tareko15 4020
#2 Enot 2215
#3 itskarudo 2160
#4 Username_1344_ 1995
#5 Matinc26 1925
Recent Solves
What's a Lattice? AaronCrighton
Adrien's Signs lemsolar
XOR Properties GGrapeJJuice
Gram Schmidt AaronCrighton
Diffie-Hellman Starter 5 jirigav
Recent Solutions
RSA Starter 5 SnowF0X 0
Passwords as Keys antidote1337 0
Bringing It All Together antidote1337 0
Diffusion through Permutation antidote1337 0
Confusion through Substitution antidote1337 0

Level Up

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